The present invention relates to devices for cutting integrated circuit package boards and, more particularly, to saw blades for cutting integrated circuit packages.
One known type of saw blade used to cut integrated circuit package boards is shown in FIG. 1, in which there is shown a circular saw blade 10. The saw blade 10 is a solid piece construction having no slots or teeth. The blade 10 has a mounting portion 12 at its center for mounting the blade 10 to the cutting machine. The blade is nickel-plated.
There are many problems associated with nickel-plated saw blades. For instance, because of the very hard nature of the electroplated nickel binder, loading of the saw blade occurs frequently when cutting package boards and unacceptable package chipping is observed. Loading results when fragments of the package board that chip during cutting stick in the surface of the saw blade, thereby changing the shape or contour of the blade. There are several effects associated with loading, including vibration of the saw blade, chipping of the package material, and a current surge on the spindle of the cutting machine.
In addition, when loading occurs, the xe2x80x9cloadingxe2x80x9d must be removed from the blade. To do so, the saw process must be stopped and the blade be xe2x80x9cdressedxe2x80x9d using a special board designed for such an application. Such measures greatly reduce the efficiency of the operation.
One solution has already been proposed as shown in FIG. 2, which provides a hard metal saw blade 20 having slots 22 cut about the circumference of the saw blade 20. The blade 20 has a mounting portion 24 for mounting the saw blade 20 to the cutting machine. The depth xe2x80x9cdxe2x80x9d of each slot is 1 mm. This prior art saw blade 20 alleviates many of the problems associated with the nickel-plated saw blade of FIG. 1. On the other hand, the saw blade 20 of FIG. 2 has problems in that the blade 20 wears very quickly, particularly those portions of the blade 20 between the slots 22. This has the effect of eliminating the slots 22 and reducing the life of the blade 20.
There is a need for a saw blade for cutting integrated circuit package boards that has a longer life and avoids chipping the board.
These and other needs are met by an embodiment of the present invention, which provides a device for cutting integrated circuit package boards comprising a circular saw blade and a plurality of slots cut in the circumference of the circular saw blade, the plurality of slots having a depth of at least approximately 2 mm.
The above needs and others are also met by another embodiment of the invention, which provides a device for cutting integrated circuit package boards comprising a circular saw blade and a plurality of first and second slots cut in the circumference of the saw blade. The first and second slots are arranged in an alternating pattern and at least one of the plurality of first and second slots has a depth of at least approximately 2 mm.
The saw blade according to the invention prolongs the life of the saw blade, eliminates loading during cutting of the integrated circuit package boards, reduces the occurrence of current surges on the spindle of the saw mechanism, and reduces chipping of the integrated circuit boards that occurs during sawing.
Additional advantages and novel features of the invention will be set forth in part in the following description and, in part, will become apparent to those skilled in the art from an examination of the following description or from practicing the invention.